<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

    <!-- <p>Not only does this paragraph have "normal" text, but it also
        <br>
        contains a line in which
        <big>
            some big text
        </big>
        is found.
        <br>
        This large text help illustrate our point.
    </p> -->

    <!-- 行内元素两端的内边距和外边距 -->
   <p>
       fdsf fdsf  fesfsfe fkposkpbbv vdffffffffff vvdddddddddddddfsf fsfodksf sdkfos sdfs
       <span>
           fds fdsfsfefpaksof fkopsafvfv vff fvf fsaffffffffefsefwsa
       </span>
   </p>

</body>
<style>
    p {
        font-size: 15px;
        line-height: 1em;
    }
    span {
        background: #999;
        padding-top: 10px;
        padding-bottom: 10px;
    }
    /* p{
        font-size: 14px;
        line-height: 1em;
    }
    big {
        font-size: 250%;
        line-height: 1em;
    } */
</style>

</html>